title: Clinical features of asthma in children differ with regard to the intensity of distal gastroesophageal acid reflux.
abstract: BACKGROUND
  The prevalence of gastroesophageal reflux (GER) in children with asthma is higher than in healthy controls, but the nature and direction of this association is unclear.
  
  
  OBJECTIVE
  The aim of our study was to assess the relationship between esophageal acid exposure and the clinical features of asthma in children.
  
  
  METHODS
  In total, 66 children (mean age 122.8 months [SD 44.89 months]) with chronic pulmonary symptoms, fulfilling diagnostic criteria of persistent asthma, underwent 24-hour esophageal pH monitoring and answered a detailed questionnaire-based survey. The questionnaire topics included environmental factors, familial history, current and previous clinical symptoms, atopy, asthma severity, and medication.
  
  
  RESULTS
  Abnormal results of 24-hour esophageal pH monitoring were found in 28 out of 66 children (42.4%). Age, sex, severity of asthma, environmental factors, spirometry results, and the type of medication did not correlate with esophageal acid exposure. However, children with abnormal pH results developed asthma significantly earlier (asthma onset 3.63 years [SD 2.52 years] vs 5.77 years [SD 3.82 years]; p < .01). Nonatopic individuals had more intensive esophageal acid exposure than atopic ones (Boix-Ochoa score 28.19 [SD 18.26] vs 18.26 [SD 12.84]; p < .048). The intensity of GER was also significantly correlated with frequent or difficult-to-control nighttime asthma attacks.
  
  
  CONCLUSIONS
  There are differences in clinical features of asthma in children with regard to the intensity of esophageal acid exposure. Symptoms of asthma in nonatopic individuals with early onset and difficult-to-control nighttime asthma attacks suggest the possibility of concomitant, clinically relevant GER.
authors.affiliation: Department of Pediatrics, Medical University of Silesia, Zabrze, Poland. jaroslaw.kwiecien@medforum.pl
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Kwiecien
authors.forename: Edyta
authors.initials: E
authors.lastname: Machura
authors.forename: Franciszek
authors.initials: F
authors.lastname: Halkiewicz
authors.forename: Jacek
authors.initials: J
authors.lastname: Karpe
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000150:complications* / Q000503:physiopathology*; D002648:Child; D002908:Chronic Disease; D002940:Circadian Rhythm; D050782:Esophageal pH Monitoring; D005260:Female; D005541:Forced Expiratory Volume; D005764:Gastroesophageal Reflux / Q000150:complications* / Q000503:physiopathology*; D006801:Humans; D006967:Hypersensitivity / Q000150:complications; D008297:Male; D008991:Monitoring, Physiologic; D012720:Severity of Illness Index; D013147:Spirometry; D011795:Surveys and Questionnaires; D013997:Time Factors